<!DOCTYPE html>

<html>
    <head>
        <meta charset="utf-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <title></title>
        <meta name="description" content="">
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <link rel="stylesheet" href="">
    </head>
    <body>
      
        <script>
      function join(){
        for (var i=0;i<arguments.length;i++){
          if(i==0){
            str=arguments[i];
          }else{
            str+="|"+arguments[i];
          }
        }
        return str;
      }
      console.log(join("hello","world"));
      function join2(...strs){
        var str="";
        for(var i=0;i<strs.length;i++){
          if(i==0){
            str=strs[i];

          }else{
            str+="|"+strs[i];
          }

return str;        }
      }
      </script>
    </body>
</html>